At present several technologies exist, which allow the monitoring of the conditions around moving vehicle and to detect presence of other vehicles and obstacles. Examples of such existing and emerging technologies are adaptive cruise control (ACC) systems and integrated safety systems. If an obstacle, such as a slower moving vehicle, is detected in front of vehicle, and it is determined on the basis of sensor information that this obstacle is too close, then the adaptive cruise control system can automatically reduce the speed of the host vehicle to match the speed of a leading slower vehicle. Speed reduction of the host vehicle is often achieved by a combination of throttle adjustment and mild braking. When the system determines that a collision cannot be avoided by limited braking, a warning is sent to the driver to initiate harder manual braking or steer to a clear lane.
Analysis of accident statistics indicates that in emergency situations, drivers usually either steer or brake, but seldom brake and steer simultaneously. This is probably due to the fact that, especially in panic situations, it is easier for most drivers to control one input at a time than two inputs simultaneously. In addition, driver maneuvers in panic situations are often too abrupt, leading to loss of vehicle control. This is particularly true when inclement weather has introduced slippery roadways reducing tire traction. Therefore, it would be desirable to have a system, which would not only brake automatically, but also smoothly change lanes in an obstacle avoidance maneuver.